# Usage

Use the Dialog component when you require your user to interact with you app and
don’t want your users to jump to a different page and break their workflow.

You should also use a dialog in cases where you need to ask for confirmation
from the user before doing a lengthy or dangerous action.
This could be a deletion of some sorts or initiating a lengthy download.

<br />

## Terminology

[BlueprintJS](https://blueprintjs.com/docs/versions/2/#core/components/dialog) pointed out in their documentation that “modal” is a misnomer for “dialog”.

> The term “modal” is sometimes used to mean “dialog”, but this is a misnomer.
> Modal is an adjective that describes parts of a UI.
> An element is considered modal if it [blocks interaction with the rest of the application](https://en.wikipedia.org/wiki/Modal_window).
> We use the term “dialog” to avoid confusion with the adjective.

<br />

## Focus Management

When opening a Dialog, focus will be brought inside the Dialog.
When using both the cancel and confirm button, the cancel button will get focus first.

When closing the Dialog, focus will be brought back to the element that was focused before opening the Dialog.
This is normally the button that triggered the Dialog.

<br />

## Default dialog example

```jsx
function DefaultDialogExample() {
  const [isShown, setIsShown] = React.useState(false)

  return (
    <Pane>
      <Dialog
        isShown={isShown}
        title="Dialog title"
        onCloseComplete={() => setIsShown(false)}
        confirmLabel="Custom Label"
      >
        Dialog content
      </Dialog>

      <Button onClick={() => setIsShown(true)}>Show Dialog</Button>
    </Pane>
  )
}
```


## Default with a danger intent

The `intent` prop determines the appearance of the confirm button, `danger` is red.

```jsx
function DangerIntentDialogExample() {
  const [isShown, setIsShown] = React.useState(false)

  return (
    <Pane>
      <Dialog
        isShown={isShown}
        title="Dialog title"
        intent="danger"
        onCloseComplete={() => setIsShown(false)}
        confirmLabel="Delete"
      >
        Are you sure you want to delete this item?
      </Dialog>

      <Button onClick={() => setIsShown(true)}>Show Dialog</Button>
    </Pane>
  )
}
```

## Internal scrolling

When content makes the dialog height greater than the available space in the viewport,
the content area will become scrollable
It will add a symmetric offset on the top and bottom — based on the `topOffset` prop.

```jsx
function InternalScrollingDialogExample() {
  const [isShown, setIsShown] = React.useState(false)

  return (
    <Pane>
      <Dialog
        isShown={isShown}
        title="Internal scrolling"
        onCloseComplete={() => setIsShown(false)}
      >
        <Pane height={1800} width="100%" backgroundColor="#ddd" />
      </Dialog>

      <Button onClick={() => setIsShown(true)}>Show Dialog</Button>
    </Pane>
  )
}
```

## Self managed close

```jsx
function SelfManagedCloseDialogExample() {
  const [isShown, setIsShown] = React.useState(false)
  return (
    <Pane>
      <Dialog
        isShown={isShown}
        title="Self managed close"
        onCloseComplete={() => setIsShown(false)}
      >
        {({ close }) => (
          <Pane>
            <Paragraph>Manage your own buttons and close interaction</Paragraph>
            <Button marginTop={16} onClick={close}>
              Self Managed Close
            </Button>
          </Pane>
        )}
      </Dialog>

      <Button onClick={() => setIsShown(true)}>Show Dialog</Button>
    </Pane>
  )
}
```

## Remove default footer

Use the `hasFooter` prop to show or hide the footer.
This will hide the confirm and cancel buttons.

```jsx
function NoFooterDialogExample() {
  const [isShown, setIsShown] = React.useState(false)
  return (
    <Pane>
      <Dialog
        isShown={isShown}
        title="No footer"
        onCloseComplete={() => setIsShown(false)}
        hasFooter={false}
      >
        No footer
      </Dialog>

      <Button onClick={() => setIsShown(true)}>Show Dialog</Button>
    </Pane>
  )
}
```

## Remove default header

Use the `hasHeader` prop to show or hide the header.
This will hide both the close icon button as the title.

```jsx
function NoHeaderDialogExample() {
  const [isShown, setIsShown] = React.useState(false)
  return (
    <Pane>
      <Dialog
        isShown={isShown}
        title="No footer"
        onCloseComplete={() => setIsShown(false)}
        hasHeader={false}
      >
        No header
      </Dialog>

      <Button onClick={() => setIsShown(true)}>Show Dialog</Button>
    </Pane>
  )
}
```

## Preserve scroll position and prevent body scrolling

Use the `preventBodyScrolling` prop to disable scrolling outside the dialog.

```jsx
function PreserveBodyScrollingDialogExample() {
  const [isShown, setIsShown] = React.useState(false)

  return (
    <Pane>
      <Dialog
        isShown={isShown}
        title="Dialog title"
        onCloseComplete={() => setIsShown(false)}
        preventBodyScrolling
        confirmLabel="Custom Label"
      >
        Dialog content
      </Dialog>

      <Button onClick={() => setIsShown(true)}>Show Dialog</Button>
    </Pane>
  )
}
```
